Maripa elongata
Rio Negro basin of Brazil
Terra firme, várzea, along riversides, high forest and old capoeiras
Fruiting specimens of this species and Maripa reticulata are difficult to distinguish. Maripa elongata apparently always has some stellate trichomes remaining on the infructescence and/or leaves, and the leaves dry yellow-green; M. reticulata does not have stellate indument, and the leaves dry dark brown-green. ONe might expect to distinguish these species by their different inflorescences, but M. elongata produces a racemose infructescence due to lowered fruit set.
Maripa elongata Ducke, Arq. Inst. Biol. Veg. 4: 60. 1938
Holotype: Brazil, Amazonas, Manaus, 24.3.1937, Ducke RB 35586 RB; isotypes G, IAN, K, NY, U, US.
Flowering: February to June
Fruiting: May to October
American Erycibeae: Systematics Vol 60. pg. 361-385 (1973)
American Erycibeae: Systematics Vol 60. pg. 361-385 (1973)
Ipomoea umbraticola superficially resembles elements of subgenus Eriospermum(hairy-seeded perennials), since the species bears seeds with white, long indumentum on the lateral seed margins. However, the species presents other traits uncharacteristic of subgenus Eriospermum such as an annual habit, herbaceous stems, and seed trichomes that are very fine and deciduous. Indeed, House (1 908) originally described the seeds as glabrous, presumably because thetrichomes had already fallen. Ipomoea umbraticola shares many characteristicswith the section Batatas, especially those of the sepals, though the species was not included in the most recent revision (Austin, 1978). The pubescent filaments may suggest close alliance with both I. batatas and I. tiliacea (Willd.) Choisy in DC. The presence of trichomes along the seed margins we interpret as representing the vestiges of a primitive character, linking the Batatas complex directly to the presumably primitive subgenus Eriospermum (Austin, 1979, 1980). Although the section was circumscribed to include only plants with "glabrous or sparsely pubescent seeds" (Austin, 1978), we now amend the concept to include I. umbraticola with marginally or laterally pubescent seeds. Ipomoea umbraticola is currently thought to be endemic to Mexico and Middle America, having been collected in Guerrero, Chiapas, Campeche, and Yucatan in Mexico to Belize, Nicaragua, and Costa Rica.